CMake: Implement configure -reduce-exports

This option maps to FEATURE_reduce_exports. The feature is on by default, except for MSVC. The reduce_exports configure test is not used in the CMake build. The <LANG>_VISIBILITY_PRESET and VISIBILITY_INLINES_HIDDEN target properties are now explicitly initialized in the qt_set_common_target_properties function, because we don't have access to the feature in QtSetup.cmake where the CMAKE_<LANG>_VISIBILITY_PRESET variables were set before. Task-number: QTBUG-85373 Change-Id: I378453f0e0665731970016170302871e20ceb4e2 Reviewed-by: Qt CI Bot <[email protected]> Reviewed-by: Alexandru Croitor <[email protected]>
JoneChenHub · Oct 5, 2020 · c09df7b · c09df7b
1 parent 313ed3d
commit c09df7b
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Showing 5 changed files with 13 additions and 10 deletions.
diff --git a/cmake/QtSetup.cmake b/cmake/QtSetup.cmake
@@ -54,13 +54,6 @@ set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 # Do not relink dependent libraries when no header has changed:
 set(CMAKE_LINK_DEPENDS_NO_SHARED ON)
 
-# Default to hidden visibility for symbols:
-set(CMAKE_C_VISIBILITY_PRESET hidden)
-set(CMAKE_CXX_VISIBILITY_PRESET hidden)
-set(CMAKE_OBJC_VISIBILITY_PRESET hidden)
-set(CMAKE_OBJCXX_VISIBILITY_PRESET hidden)
-set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
-
 # Detect non-prefix builds: either when the qtbase install prefix is set to the binary dir
 # or when a developer build is explicitly enabled and no install prefix is specified.
 # This detection only happens when building qtbase, and later is propagated via the generated

diff --git a/cmake/QtTargetHelpers.cmake b/cmake/QtTargetHelpers.cmake
@@ -175,6 +175,14 @@ endfunction()
 # Set target properties that are the same for all modules, plugins, executables
 # and 3rdparty libraries.
 function(qt_set_common_target_properties target)
+    if(QT_FEATURE_reduce_exports)
+        set_target_properties(${target} PROPERTIES
+            C_VISIBILITY_PRESET hidden
+            CXX_VISIBILITY_PRESET hidden
+            OBJC_VISIBILITY_PRESET hidden
+            OBJCXX_VISIBILITY_PRESET hidden
+            VISIBILITY_INLINES_HIDDEN 1)
+    endif()
    if(FEATURE_static_runtime)
        if(MSVC)
            set_property(TARGET ${target} PROPERTY

diff --git a/cmake/configure-cmake-mapping.md b/cmake/configure-cmake-mapping.md
@@ -61,7 +61,7 @@ The effort of this is tracked in QTBUG-85373 and QTBUG-85349.
 | -R <string>                           | -DQT_EXTRA_RPATHS=path1;path2                     |                                                                 |
 | -rpath                                | negative CMAKE_SKIP_BUILD_RPATH                   |                                                                 |
 |                                       | negative CMAKE_SKIP_INSTALL_RPATH                 |                                                                 |
-| -reduce-exports                       |                                                   |                                                                 |
+| -reduce-exports                       | -DFEATURE_reduce_exports=ON                       |                                                                 |
 | -reduce-relocations                   | -DFEATURE_reduce_relocations=ON                   |                                                                 |
 | -plugin-manifests                     |                                                   |                                                                 |
 | -static-runtime                       | -DFEATURE_static_runtime=ON                       |                                                                 |

diff --git a/configure.cmake b/configure.cmake
@@ -642,7 +642,7 @@ qt_feature("enable_gdb_index"
 qt_feature_config("enable_gdb_index" QMAKE_PRIVATE_CONFIG)
 qt_feature("reduce_exports" PRIVATE
     LABEL "Reduce amount of exported symbols"
-    CONDITION NOT WIN32 AND CMAKE_CXX_COMPILE_OPTIONS_VISIBILITY
+    CONDITION NOT MSVC
 )
 qt_feature_definition("reduce_exports" "QT_VISIBILITY_AVAILABLE")
 qt_feature_config("reduce_exports" QMAKE_PUBLIC_QT_CONFIG)

diff --git a/util/cmake/configurejson2cmake.py b/util/cmake/configurejson2cmake.py
@@ -123,7 +123,6 @@ def map_tests(test: str) -> Optional[str]:
         "spe": "TEST_subarch_spe",
         "vsx": "TEST_subarch_vsx",
         "openssl11": '(OPENSSL_VERSION VERSION_GREATER_EQUAL "1.1.0")',
-        "reduce_exports": "CMAKE_CXX_COMPILE_OPTIONS_VISIBILITY",
         "libinput_axis_api": "ON",
         "xlib": "X11_FOUND",
         "wayland-scanner": "WaylandScanner_FOUND",
@@ -952,6 +951,9 @@ def get_feature_mapping():
                 },
             ],
         },
+        "reduce_exports": {
+            "condition": "NOT MSVC",
+        },
         "release": None,
         "release_tools": None,
         "rpath": {